Major credit card firms appealed Monday for calm after it was learned that personal information on tens of thousands of Japanese card holders may have been leaked as a result of a security breach in the United States.
The firms stressed that they are insured for such a contingency and that users will not be charged if they promptly inform the card issuers of any strange purchases on their credit cards.
The attack is believed to have exposed the numbers of 13.9 million MasterCards and an unknown number of other brands of cards, including American Express.